Centrifugal machine



Oct. 2, '1934. H. a ELROD 1,975,539

'CENTRIFUGAL MACHINE Filed May 1931 s Sheets-Sheet 1 gnaw/nth Get, 2, 1934. H. E. ELROD CENTRIFUGAL MACHINE Filed May 4, 1931 3 Sheets-Sheet 2 3 Sheets-Sheet 5 'F iled May 4, 1931 Patented Oct. 2, 1934 1,975,539 CENTRIFUGAL MACHINE Henry E. Elrod, Houston, Tex. Application May 4,1931, .Serial No. 534,956

12 Claims. (01. 210-69) This invention relates to .centrifugal machines, and more particularly to the type embodying a continuous. feed'andidis'charge. v

It is an object of my invention to provide a L'-.1u'igged v machine adapted to separate liquid and solid" matter from a mixture of the two.

-It isa further object of my invention to provide amachine. which is capable of operating at high. centrifugal pressures without rapid demi'terioration of the parts.

More'specifically it is an object of my invention to provide-a machine peculiarly adapted for-the dewatering of sewage sludge, with a convenientmode of disposition of its constituents. In the-treatment of sewage'for municipalities, the-drying of. the sewagesludge,- both from raw and" activated sewages, vand from the two combined, presents a most difficult "and expensive problem. Many methods of drying sludges have beenrdevised, but to datenone is quite satisfac tory, I or economical. Centrifuges have come nearer. solving the problem, none has proved satisfactory in practice, par.- ticularly on account of the fact that the cenrtrifugesdo not-strain out sufficient of the solids in the wet sludge to obviate the necessity for further treatment of theexpressed liquor, and that the operation of the centrifuges isnot continuous, it being neoessary'to stop, operations .'to"unload the" centrifuge-of. its dewatered sludge. The centrifuges-of the'prior art have been very expensive machines, also.

The .machine also possesses a distinct utility for the function of removing sand and other ex-- Ltraneous. matterfrom liquid mud as used' in the oil fields for drilling Y operations. This adaptation has .a great field, as the mud is a very expensivecommodity.- When the mud is.used-,. it accumulates sand and chippings of groclg. which destroy thepistons of the'pumps which are used to force down the'f mud? into-the astit'utes the inner surface of said peripheral wall. It is a further object of my invention topro-- deep drilling holes.

videcamelszhair cloth *as a straining medium,

which althoughexpensive initially, proves econ-- omical because-ofits durability under highpressure, .operations... r

Withtheforegoing .and other objectsin view,

the invention willbe .more fully described hereinafter and will .be. more particularly pointe outeinlthe claims-appendedhereto- In .thedrawings,

proved centrifugal. machine in connection :with

the-associated system in. elevation; I

as to expense, but

chine; 1

Fig. 3 represents a sectional view of a modification of the machine illustrated in Fig. 1;

Fig. 4 is an elevation, partly in section of a modified embodiment of my machine;

Fig. 5 is an end view thereof.

In Fig. 1,

Fig. 2 is; an end view of the centrifugal ma-- element 1 represents a tank or any other conventional container adapted to hold.

liquor such as wet sludge from sewage. A stufiing box 2 is attached to tank 1, to accommodate the hollow rotating shaft 3. Tank 1 and its stuiiing box.-2 -may bereplaced-by the discharge from any conventional pump, a pipe line, reservoir, or other source of wet sludge, or the like,-

from which the wet sludge or equivalent material may be transferred to hollow shaft 3. Hol- I low shaft 3 is supported on conventional journal bearings 4 disposed on suitable stands or pillows.

5. Fixedly disposed on shaft 3 is-a pulley or gear element 6,

throughwhich rotary motionis imparted to shaft 3 from some conventional prime. mover.

Centrifuge '7 isfixedly attached to one end of shaft 3 substantially as shownso that it will rotate therewith. This centrifugal-machine consists of an end. wall. 8 which. isattached to the shaft 3. ,Oppositely disposed to this end wall is another one '9 which may have cast. therewith or otherwise attachedto itradial septa or partitions.

10,.sh0Wn in Fig. 2, of any desired number. These septa 10 are closely fittedto wall 8 by suitable fasteningmembers such as. bolts 11, as illustrated. Thematerials used for thesewalls and septa may be ofanytype common tosuch machines. In the modification shown in Fig. 1 the. external peripheral ring orwall 12 has a curved portion which is perforated to allow. the ex.- pressed liquors .to pass through. Anotherperforatecl peripheral ringl i, made up of smooth material .conforming in shape to ring 12,. con- Thesetwoperforated walls are-rigidly connected tothe wall 8 and are furthermore bracedupon the. opposite side by an annular ring. 13. Be-

tween the peripheral walls 12 and 14,-is disposed a filteringmedium such as wire mesh or prefistic of this type'of machine better than does any other "filtering'medium. The cross sectional diameter of end wall 9"is less than that of the Fig. 1 represents a sectional view-ofamy im-- peripheral wall in order to provide a relief passageii=25:fortheextrusion of the solid matter which is'forced out; The. modification in Fig.

3 illustrates a straight type of a peripheral wheel. In this case the end wheel 9 is formed with a lip 16 to provide the proper extrusion channel for the solid material. Otherwise, the elements of this modification correspond to those illustrated in Fig. l.

Centrifuge '7 is entirely enclosed, except as shown, by a suitable hood or cover 17, the object of which is to catch and drain to the outlet 18, the liquor passing into said cover from the interior of the centrifuge 7. Hood 1'? is cut away in the circular form at the right of Fig. 1, and a lip 19 is turned inwardly around the complete circumference, to insure complete entrapment of the liquid material. The bottom of hood 17 forms a pan 20 adapted to hold the liquor, which may be drained off through outlet 18.

Adjacent the mouth of the centrifuge, formed to the centrifuge, and the centrifugal force operates to express the liquor from the solids of the sludge through perforations in plate 14 and through filter medium 15 and ring 12, out into cover 17, where it will fall into pan 20, thence through outlet 18 to suitable storage or to waste. The lip 19 of cover 17 will trap all splashing, or trickling liquor and prevent its escape through the side opening in cover 17. As liquor is expressed from the sludge in centrifuge 7 the vol- .ume of such sludge will be reduced and additional wet sludge will fiow into centrifuge '7 from tank 1, or other source, through hollow shaft 3, to keep centrifuge 8 filled.

By virtue of the force of the centrifugal pressure exerted on the mass of sludge in centrifuge 7 between walls 8 and 9, the dewatered sludge near the inner periphery of wall 12 will push out through the annular opening at 25 and be forced centerward until it reaches the inner edge of ring 13, when plough 21 will catch it and throw it upon conveyor 22, or upon the floor to be r moved manually. The above operation refers to Fig. 1, but is applicable to Fig. 3 also.

The embodiment illustrated in Figs. 4 and 5 provides a feature for continually clearing the interior surface of the peripheral ring or wall of the accumulated material. The structure illustrated in Fig. '1 embodies similar elements to those correspondingly shown in Figs. 1 and 3. However the chamber for the rotating material is of difierent design. As in Fig. 1, end wall 8 is fixed to hollow shaft 3. The peripheral wall comprising a filtering medium is fixed to wall 8 and reinforced by ring 13. The cooperating wall 3 0 opposite to wall 8 is independently mounted upon a shaft 31, which is co-axial with shaft 3. This wall is illustrated as circular, and may be of plane or concave form. Curved blades 35 are fixed to wall 30, the shapes of which conform to the shape of the inner walls of the rotating chamber, andwhich upon the relative rotation of the centrifuge and the blades, just clear the centrifuge walls.

Rotary motion is imparted to shaft 31 and consequently to elements 30 and 35 by means of 2.

countershaft 34 displaced from the main shaft 3 and driven therefrom by means of a gear or pulley 36 upon the latter, through a suitable belt or equivalent transmission. Another pulley 37 upon shaft 34 imparts the rotary motion of the latter to shaft 31 by means of a pulley 38 thereupon. The transmission system is so designed that shaft 31 rotates in the same direction as shaft 3 but at a lesser speed.

The machine operates in the manner explained in regard to Figs. 1 and 3, with the additional function that the blades 35, rotating at a lesser speed than the centrifuge casing, act as plows, and loosen the mass of solid material for extrusion thereof through annular channel 40. The inclination of the plows may be designed to aid in this effect. The blades 35 will keep the filter cloth 15, or if desired the protective ring 14, as shown in Fig. l, scraped clean of the dewatered sludge, to render more positive the contintious operation of the machine. T Y

It is presumed that the centrifuge may be rotated as a speed sufficient to produce a centrifugal pressure, at the periphery, of several hundred pounds per square inch, which may be 400, which corresponds with the pressures obtained in practice by mechanical presses, such as are used to express oil from cotton seed, etc. However, if such pressure is not readily obtainable, economically, in the given centrifuge, the economical :3

pressure may be augmented, at will, by creating an initial pressure through hollow shaft 3 by means of a pressure pump instead of the gravity flow provided by the tank 1. Given an initial pressure, as described, of 100 pounds per square inch, and a centrifugal pressure of 300 pounds per square inch, an ultimate pressure, at the periphery in the centrifuge, of 400 pounds per square inch will be had.

In conjunction with such high pressures, it is 5 if out departing from the spirit thereof, such i changes and modifications being restricted only by the scopeof the following claims.

Having thus described my invention what I claim is:

1. In a centrifugal machine, a rotatable member comprising an end wall, a peripheral wall fixed to said end wall, a second end wall oppositely disposed and rigidly connected to said first wall, the edge of said second wall being displaced from said peripheral wall, said peripheral wall having perforations therein extending from said first end wall to at least the plane of said second end wall.

2. In a centrifugal machine, a rotatable member comprising an end wall, a second end wall oppositely disposed and rigidly connected to said first wall, an outwardly curved peripheral wall fixed to said first end wall and extending on both sides of and displaced from said second wall,

said peripheral wall having perforations therein extending from said first end wall to at least, the portion thereof opposite the peripheral edge of said second wall.

3. In a centrifugal machine, a rotatable member comprising an end wall, a second end wall oppositely disposed and rigidly connected to said first wall, a peripheral wall fixed to said first end wall and extending on both sides of and displaced from said second Wall, said peripheral wall having perforations therein extending from said first end wall to at least the plane of said second wall and a plow cooperating with said rotatable member.

4. In a centrifugal machine, a rotating series of chambers formed of one end wall mounted upon a hollow rotatable shaft, a second end wall complementarily disposed and connected to said first wall, radial septa disposed between the said end walls, a peripheral wall contacting with said first end wall and concentrically displacedfrom the second saidperipheral wall having a reticulated portion extending from said first end Wall to at least beyond the edge of said second wall and means for introducing a mixture of liquid and solid matter into said chambers to separate the same.

5. In a centrifugal machine, a hollow horizontally rotatable shaft, a rotatable member comprising an end wall disposed at the end of said shaft, a series of radially disposed chambers communicating with said shaft at said end adapted to receive a mixture of solid and liquid matter from said shaft, reticulated means rigidly connected to said end wall disposed at the radial extremities of said chambers for straining out the liquid matter, said end wall and reticulated means being so disposed as to provide a relief passage at said extremities for allowing the extrusion of solid matter from said chambers.

6. In a centrifugal machine, a hollow horizontally rotating shaft, a rotatable chamber comprising an end wall disposed beyond said shaft adapted to receive a mixture of solid and liquid matter from said shaft, a reticulated means disposed at the radial extremity of said chamber for straining out the liquid matter, said end wall and reticulated means being so disposed as to provide a relief passage at said extremity for allowing the extrusion of solid matter from said chamber.

7. The combination as claimed in claim 6 wherein is provided a shield surrounding said rotatable chamber adapted to confine the liquid matter for disposition.

8. In a centrifugal machine, a rotatable chamber comprising an end wall and a reticulated peripheral wall, means for rotating said chamber, a second wall, independently mounted, and disposed within said chamber opposite said end wall with the edge thereof displaced from said peripheral wall, a blade fixed to said second wall transversely thereof and adjacent said peripheral wall adapted to clear said peripheral. wall of the material accumulated against it, and means for effecting relative rotary movement between said rotatable chamber and said blade.

9. In a centrifugal machine, a rotatable member comprising an end wall, a second end wall oppositely disposed and rigidly connected to said first wall, an outwardly curved peripheral wall fixed to said first end wall and extending on both sides of and displaced from said second wall, the lateral extremities of said peripheral wall overlying the peripheral edge of said second wall upon opposite sides thereof, said peripheral wall furthermore having perforations therein extending from said first end wall to the opposite extremity thereof laterally beyond and radially within the peripheral edge of said second wall.

10. In a centrifugal machine, a hollow rotatable shaft, a rotatable member comprising an end wall disposed at the end of said shaft, a reticulated peripheral wall fixed to said end wall defining a chamber for receiving a mixture of solid and liquid matter from said shaft, a second wall disposed within said chamber opposite said firstmentioned end wall with the edge thereof displaced from said peripheral wall, at least one cleaning member extending transversely of said second wall and peripheral wall mounted on said second wall in proximity to said peripheral wall, means for rotating said shaft and chamber, and means for rotating said second Wall at a speed differing from that of said peripheral wall of the chamber, whereby said peripheral wall is cleaned by the movement of said cleaning member.

11. In a centrifugal machine, a rotatable chamber comprising an end wall and a reticulated peripheral wall, a second wall, independently mounted, and disposed within said chamber opposite said end wall with the edge thereof displaced from said peripheral wall, means for rotating said chamber comprising a hollow shaft for introducing the material into said chamber at said end wall and directing it towards said second wall, and at least one blade fixed to said second wall transversely thereof and adjacent said peripheral Wall adapted to clear said peripheral wall of the material accumulated against it by means of the relative movement between said chamber and said blade.

12. In a centrifugal machine, a rotatable chamber comprising an end wall and a reticulated peripheral wall, a second wall, independently mounted, and disposed within said chamber 0pposite said end wall with the edge thereof displaced from said peripheral wall, means for rotating said chamber comprising a hollow shaft for introducing the material into said chamber at said end wall and directing it towards said second wall, and a plurality of cleaning members extending transversely of said second wall and peripheral wall and mounted on said second wall in proximity to said peripheral wall adapted to clear the latter of the material accumulated against it.

HENRY E. ELROD. 

